[BUG] `checkIfURLIsAvailable` rejects because ECONNREFUSED 127.0.0.1:8080

I suspect there is a simple setting needing changed to allow the extension CORS access to `locahost:8080`, but am unsure where/what.

Locate checkIfURLIsAvailable in the TypeScript extension and trace how it handles the request to localhost:8080; first reproduce the reported ECONNREFUSED failure. Done means the extension can check the intended local URL without the reported failure, with the CORS behavior clarified or corrected.

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